A windshield wiper structure is usually installed close to a windshield of a motor vehicle, and a wiper blade thereof is driven to swing back and forth within a generally sector-shaped wiping area. The wiper blade has a wiper strip made of a rubber material for wiping off deposited dust or water, such as wiping accumulated rainwater or snow from the windshield.
FIG. 1 is an exploded perspective view of a conventional windshield wiper blade structure; and FIG. 2 is a fragmentary, enlarged and assembled sectional view of the conventional windshield wiper blade structure of FIG. 1. As shown, the conventional windshield wiper blade structure includes a support strip 11, two wind deflector strips 12 disposed on a top of the support strip 11, a wiper strip 13 disposed on a bottom of the support strip 11, two end caps 14 fitted to two longitudinally opposite ends of the associated support strip 11 and wiper strip 13, a bracket 15, and a protective cover 16 covering the bracket 15. The support strip 11 is provided near each of the two opposite ends thereof with an elastic hooking portion 111, which is formed by punching with a free end upward projecting from the top of the support strip 11 at an inclination to provide a degree of elasticity. Each of the end cap 14 is internally provided at a predetermined position with a notch 141 corresponding to the elastic hooking portion 111, such that when the end cap 14 is fitted onto one end of the support strip 11, the notch 141 is engaged with the elastic hooking portion 111 to thereby hold the end cap 14 to the end of support strip 11 and the wiper strip 13 to the bottom of the support strip 11. With these arrangements, the wiper strip 13 is prevented from sliding off the support strip 11. The windshield wiper blade structure can be detachably connected to a wiper bracket provided on the motor vehicle, and driven to swing back and forth on the windshield to wipe off rainwater. After having been swung back and forth on the windshield to wipe off rainwater or snow over a long period of time, the wiper strip 13 tends to become deformed or damaged due to elastic fatigue and must be replaced with a new one. In the above described conventional windshield wiper blade structure, the end caps 14 are not detachable from the support strip 11 once they are engaged with the elastic hooking portions 111. The wiper strip 13 can be removed from the support strip 11 only when the end caps 14 and the elastic hooking portions 111 are destroyed to separate the end caps 14 from the ends of the support strip 11. That is, when the wiper strip 13 is aged or damaged, the whole set of the conventional windshield wiper blade structure must be replaced. This is of course not economical to do so.
In addition, since the support strip 11 is made of a relatively tough material and has a relatively large thickness, it is uneasy to punch the support strip 11 at two ends thereof to form the two elastic hooking portions 111. Thus, the conventional windshield wiper blade structure is manufactured at increased cost.